The series follows the adventures of lighthearted Jean-Paul Moulin, a police Commissaire, and his team as they solve crimes.

Journalist Claude Leroy (Jacques Champreux) reports that a secret society, The Companions of Baal, is behind a hold-up in the small town of Blaingirey. They are led by the Grand Maître Hubert de Mauvouloir (Jean Martin). An adorant of Lucifer, he aims to enslave the world. Accompanied by their acolyte, Pierrot Robichat (Gérard Zimmermann), and a young girl, Françoise Cordier (Claire Nadeau), Claud...

The series follows the adventures of lighthearted Jean-Paul Moulin, a police Commissaire, and his team as they solve crimes.